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A geometric optics approximation is used to compute the near-infrared absorption by particles containing internal scatterers, such as bubbles, occlusions, or other refractive-index inhomogeneities. If the probabilities of absorption and scattering are comparable, absorption by a weakly absorbing particle can be increased substantially beyond that in the absence of internal scattering. Although the geometric optics approach limits the range of applicability of the results, the effects are not necessarily restricted to particle dimensions and wavelengths where geometric optics is accurate.

The EU INTERREG-IV Programme (2007-2013) is an important source of external competitive funding for a range of knowledge-based marine projects promoting regional and cross-border co-operation and development. During the period 2007-2010, 29 INTERREG-IV projects (including two preparatory actions) with Irish participation were approved for funding. The total value of these projects is circa €75.5m with over €12.3m in grant-aid going to the Irish partners. This directory provides a summary of each of these 29 projects. Many of these projects in turn contribute to the implementation of research, development and innovation priorities identified in Ireland's national Strategy for Science, Technology and Innovation (SSTI: 2006-2013) and its marine component, the Sea Change Strategy (2007-2013)., Funder: European Union

The EU Framework Research Programme (FP), and in the current context the 7th Framework Programme (FP7: 2007-2013), continues to be a major source of competitive R & D funding for Irish marine researchers. The 2009 Supplement provides information on new FP7 research awards granted in 2009 to Irish marine researchers and up-dates the 2007-2008 Report published in June 2009. Seventeen research projects are profiled including three 2008 awards (STANDPOINT, WAVETRAIN II and AIRSEA) and fourteen 2009 awards bringing total participation in FP7 over the period 2007 to 2009 to 43 projects worth over €17.5 million in grant-aid. This figure is already in excess of the €10.6m (59) projects won in the FP6 (2002-2006) Programme and represents 11.5% of the total Irish drawdown to-date (FP7: 2007-2009) of €152.7million., EU Framework Research Programme (FP), and in the current context the 7th Framework Programme (FP7: 2007-2013), Funder: Marine Institute

It is commonly observed that natural multiple-scattering media such as sand and soils become noticeably darker when wet. The primary reason for this is that changing the medium surrounding the particles from air to water decreases their relative refractive index, hence increases the average degree of forwardness of scattering as determined by the asymmetry parameter (mean cosine of the scattering angle). As a consequence, incident photons have to be scattered more times before reemerging from the medium and are, therefore, exposed to a greater probability of being absorbed. A simple theory incorporating this idea yields results that are in reasonable agreement with the few measurements available in the literature, although there are differences. Our measurements of the reflectance of sand wetted with various liquids are in reasonably good agreement with the simple theory. We suggest that the difference between reflectances of wet and dry surfaces may have implications for remote sensing.